Conventional pliers consist of two elongated pincer members which are pivotally connected, one to the other, with those portions of the elongated members rearwardly of the pivot forming handles suitable for gripping by a user's hands, and those portions of the elongated members forwardly of the pivot forming a gripping device consisting of two geometrically similar gripping arms or members, which gripping arms or members terminate in a common narrow end. The abutting surfaces of the end portions of the gripper members are almost invariably serrated to assist in obtaining a purchase on an article or work piece to be gripped.
In operation the pliers may be used merely to grip an object and pull it with respect to a resisting force, or hold an object stationary while another component of the object is displaced, as by pulling or pushing with respect to it. Another very common use of pliers is to grip an elongated object, such as a wire or rod-like element, and break the gripped elongated object next to the gripped location by flexing the pliers with respect to the axis of the gripped object. If the gripped object is brittle, such as a thin glass rod, the separation will occur instantly upon the first flex of the pliers with respect to the object and, almost without exception, right at the location where the edge of the pliers contacts the elongated object.
In the more usual situation of separating a more flexible object, such as a steel or copper wire, the pliers may have to be flexed a number of times until stress fracture of the flexible work piece occurs. Generally speaking the larger the object to be separated and the greater flexibility it has, the larger will be the number of flexing movements which must occur before separation takes place.
One difficulty with present pliers when used in connection with flexible objects such as copper wire is that slippage of the serrated surfaces of the gripping arms of the pliers which are in contact with the object to be separated frequently occurs. As a result the final break point of the wire or other object occurs at a location on the wire which is remote from the location next to which the gripper arms of the pliers initially contacted the wire. Hence, the objective of separating a wire at location X may not be achieved because a separation eventually takes place at a location Y which is spaced a distance Z from the initially desired location X.
Conventional pliers are usually quite capable of picking up objects of substantial size, such as approximately 1/16" square or even somewhat smaller objects. However the conventional pliers almost invariably have a blunt or rounded nose, often of about 1/16" thick in width or diameter, depending on the geometrical shape of the working ends of the gripper arms, and hence picking up very small objects, say on the order of about 1/64" or less, can be very difficult if not impossible. As is well known there are numerous industries in which a general purpose pliers is needed; that is, a pliers which can quickly and efficiently do heavy tasks such as bend wire or pull a workpiece with as much force as an individual can supply and, in the next moment, performing a very delicate pickup of a very small workpiece. No pliers are known which can perform all of the above described tasks by a single tool and hence a need exists for pliers which are very rugged and, at the same time, very sensitive and delicate so as to be able to perform the complete spectrum of tasks ranging from heavy pulling and thick wire flex-separation to pickup of the most delicate and smallest components, such as watch components, thread-like elements or even flat sheets.
It will also be appreciate that conventional pliers have only one gripping means, namely, a plurality of serrations on the inside, facing surfaces of the end portions of the gripping arms. Although this single gripping means is sufficient for a large number of common tasks, the more demanding and or unusual tasks can often not be accomplished with conventional pliers, no matter how fine the quality thereof.